The present invention relates generally to a method of making laminated shingles, each comprising plural layers, and more particularly to a method of making these types of shingles, wherein an underlayment and an overlayment of each shingle are formed from different rolls of substrate material. The present method facilitates manufacture of laminated shingles each having an underlayment and overlayment with substrates of potentially differing thicknesses, differing asphalt compositions and/or differing granule formulations adhered thereto.
Roofing shingles have found widespread acceptance in the construction industry for covering of roof structures. A typical shingle comprises a web in the form of a fiberglass mat, or like material, which is coated with an asphalt composition to substantially impregnate the substrate. Granules, typically crushed rock with a pigmented ceramic coating, are applied to the top of the substrate, while sand or talc is applied to the back. The granules are pressed into the surface of the asphalt so that they are adhered thereto, with the web of material typically thereafter cooled by application of water sprays. The web of material is thereafter cut to length, and individual shingles stacked and packaged for subsequent storage and shipment.
While shingles formed in accordance with the above process can be provided in varying thicknesses, with varying colors and compositions of granules applied thereto, shingles formed by a lamination process provide a wide variety of aesthetic effects. These types of shingles typically include plural layers comprising an underlayment and overlayment arranged in at least partially overlapping relationship. By profiling an edge of the overlayment to a non-linear configuration, thus exposing portions of the underlayment, different decorative effects can be achieved.
Heretofore, manufacture of laminated shingles has typically been effected by formation from a single web of material. The web is processed in a generally conventional manner, with application of an asphalt composition thereto, and subsequent adherence of granules across the width of the web. Since a single web is employed for manufacture of the laminated shingles, the asphalt composition and the granule formulation adhered thereto are applied essentially uniformly across with width of the web. The single web is thereafter subdivided, typically to provide a pair of underlayments, and a pair (or two pairs) of overlayments for respective lamination to the underlayments.
While laminated shingles can be achieved to create a wide variety of aesthetic effects, including enhanced relief, the above-described process lacks versatility in that the substrate, asphalt composition, and granule formulation for the underlayment and overlayment of each laminated shingle are essentially identical, by virtue of the formation of the shingles from a common web. The present invention contemplates a method of making laminated shingles which greatly enhances the versatility with which such shingles can be manufactured.
A method of continuously making laminated shingles in accordance with the present invention contemplates that an underlayment and an overlayment of each laminated shingle are formed from different rolls of substrate material, and can be processed by different techniques, including application of differing asphalt compositions and/or differing granule formulations. Not only can the thickness of the underlayment and overlayment of each shingle be selected to be different, a wide variety of aesthetic effects can be achieved by varying the color formulation of the granules applied to each of the underlayment and overlayment. Differing asphalt compositions can be applied to each of the underlayment and overlayment of each shingle further enhancing the versatility of the present method.
In accordance with the disclosed embodiment, the present method of making laminated shingles comprises the steps of providing a first roll of substrate material to provide an underlayment web to form an underlayment for each of the laminated shingles. The method further comprises providing a second roll of substrate material to provide an overlayment web to form an overlayment for each of the laminated shingles. As noted, each of the substrates of material, typically comprising fiberglass mat or other material, can be selected as may be desired for the specific laminated shingle being made, including selection of substrate materials having differing thicknesses.
The present method further contemplates subdividing the underlayment web along the length thereof into plural subdivided underlayment web portions. Similarly, the overlayment web is subdivided along the length thereof into plural subdivided overlayment web portions. Lamination of respective ones of the underlayment web portions and overlayment web portions is effected to form plural laminated webs, with individual shingles formed by transversely cutting each of the laminated webs into individual laminated shingles.
In accordance with typical shingle-forming techniques, an asphalt coating composition is applied to each of the underlayment and overlayment substrates prior to the subdivision thereof, with the present method further comprising application of a granule formulation onto the asphalt coating on each of the underlayment and overlayment webs. By virtue of the formation of the underlayment and overlayment of each laminated shingle from different rolls of substrate material, the present method facilitates application of differing amounts of the asphalt coating composition, per unit of surface area, to each of the underlayment and overlayment webs. If desired, different asphalt compositions may be applied to each of the underlayment and overlayment webs. Similarly, the granule formulation applied to the underlayment web can differ from the granular formulation applied to the overlayment web, thus permitting the colors of the formulations to be different, or the formulations to be otherwise varied for desired aesthetic or functional effects. As noted, the substrate which forms the underlayment and overlayment webs can be of differing thicknesses for each of the webs, thus providing further versatility in the manufacture of the laminated shingles.
As will be appreciated, laminated shingles formed in accordance with the present invention include plural layers comprising an underlayment and an overlayment arranged in at least partially overlapping relationship, and include an adhesive for bonding the underlayment and overlayment to each other. Each of the underlayment and overlayment comprises a substrate, an asphalt coating composition on the substrate, and a granule formulation adhered thereto. In accordance with the present invention, the substrate of the underlayment can differ in thickness from the substrate of the overlayment, with the granule formulation adhered to the underlayment differing, such as in color, from the granule formulation adhered to the overlayment. If desired, the amount of asphalt coating applied to each of the underlayment and overlayment may differ and/or the asphalt composition applied to the underlayment may differ from that applied to the overlayment.
Other features and advantages of the present invention will become readily apparent from the following detailed description, the accompanying drawings, and the appended claims.